1. Field of the Invention
This invention relates to an image printing method and apparatus, as well as to a copying apparatus, in which an image is printed on the basis of entered image information by scanning a printing head having a plurality of printing elements (nozzles or heating elements) arranged in a direction substantially perpendicular to the scanning direction of the printing head.
2. Description of the Related Art
In an ink-jet printer known in the art, an ink-jet head having a plurality of nozzles arranged in a subscan direction is mounted on a carriage and the carriage is made to scan in a main-scan direction to perform printing. When printing is performed using an ink-jet head, images on a plurality of lines are capable of being printed simultaneously on a recording medium such as recording paper by a single scan of the carriage. The width of the image thus printed generally is referred to as a "band".
With an ink-jet head of this kind, however, 128 nozzles, for example, are arranged at intervals of about 60 .mu.m, and inevitably a variance develops in the accuracy with which ink is jetted from each of the nozzles. This variance in the jetting accuracy appears as unevenness in the printing density of the printed image. Such uneven density gives rise to a decline in the image quality of the printed image.